Expression of alpha6 and beta4 integrin subunits on human endometrium throughout the menstrual cycle and during early pregnancy.
OBJECTIVE
To evaluate the expression of alpha6 and beta4 integrin subunits on surface and glandular endometrium throughout the menstrual cycle and during early pregnancy.


METHODS
Second Department of Obstetrics and Gynecology, University of Catania, Catania, Italy.


METHODS
Thirty-two women. Nineteen of the women regularly menstruated in different phases of the cycle, and 13 were in the sixth to ninth week of gestation and required voluntary abortion.


METHODS
Endometrial specimens collected during endometrial biopsy, hysterectomy, or voluntary abortion.


METHODS
Immunohistochemical staining for alpha6 and beta4 integrin subunits in endometrial tissues.


RESULTS
Both subunits (poorly expressed in preimplantation days) reached a significant peak on the endometrial surface during the implantation window, which tended to disappear in the postimplantation phase. On glandular endometrium they exhibited an opposite trend, showing high levels in the preimplantation and postimplantation days, whereas their expression decreased during the implantation window. The two subunits tended to disappear in early pregnancy.


CONCLUSIONS
alpha6 and beta4 integrin subunits are uniformly distributed and highly expressed on the endometrial surface during the implantation window; they decreased dramatically in the postimplantation phase. These results could suggest involvement of integrin-extracellular matrix components in blastocyst-endometrium interaction during the early stages of implantation.
Lanteri
E
E
Second Department of Obstetrics and Gynecology, University of Catania, Italy.
Pistritto
M
M
Bartoloni
G
G
Cordaro
S
S
Stivala
F
F
Montoneri
C
C
D000328:Adult; D015703:Antigens, CD / Q000378:metabolism*; D047108:Embryonic Development / Q000502:physiology; D004717:Endometrium / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D039503:Integrin alpha6; D039663:Integrin beta4; D008597:Menstrual Cycle / Q000378:metabolism*; D008875:Middle Aged; D011247:Pregnancy / Q000378:metabolism*; D011261:Pregnancy Trimester, First; D013194:Staining and Labeling; D014018:Tissue Distribution
D015703:Antigens, CD; D039503:Integrin alpha6; D039663:Integrin beta4